diff --git a/lib/snowflake/generator.ex b/lib/snowflake/generator.ex
index 51d48c9..ab9d80b 100644
--- a/lib/snowflake/generator.ex
+++ b/lib/snowflake/generator.ex
@@ -48,7 +48,8 @@ defmodule Snowflake.Generator do
 
   defp create_id(ts, machine_id, seq) do
     << new_id :: unsigned-integer-size(64)>> = <<
-       ts :: unsigned-integer-size(42),
+       0 :: unsigned-integer-size(1),
+       ts :: unsigned-integer-size(41),
        machine_id :: unsigned-integer-size(10),
        seq :: unsigned-integer-size(12) >>